Driving device, image blur correction device and camera equipment

Abstract

The present invention relates to a driving device, an image blur correction device and a camera apparatus. A driving device is provided, which reduces the return force of the return center when the movable unit is moved relative to the fixed unit, and suppresses the load of the actuator driving the movable unit. The driving device includes: a fixed unit; a movable unit, which is arranged to be able to move relative to the fixed unit within a predetermined range in a plane; a plurality of rolling members, which are arranged between the fixed unit and the movable unit; an actuator, which is configured to drive the movable unit; and a force applying unit, which is configured to apply force to the movable unit toward the fixed unit via the rolling members. The force applying unit includes a magnet and a magnetic body. One of the magnet and the magnetic body is held by the movable unit, and the other of the magnet and the magnetic body is held by the fixed unit. When viewed from a direction orthogonal to the plane, the range in which the magnet can move when the actuator is driven to move the movable member does not protrude from the end of the magnetic body.

Description

Technical Field

[0001] The present invention relates to a driving device, an image blur correction device, an image pickup apparatus, and a lens barrel, and more particularly to an image pickup apparatus and a lens barrel equipped with a driving device using a voice coil motor. Background Art

[0002] Conventionally, a driving device for moving a movable unit within a plane relative to a fixed unit is known, and as a configuration for generating a driving force for driving the movable unit, there is a configuration called a voice coil motor (VCM) method.

[0003] In the VCM method, a magnet is arranged at one of a movable unit and a fixed unit, a coil is arranged at the other of the movable unit and the fixed unit, and a driving force is generated by energizing the coil in a magnetic circuit formed by the magnet. For example, one of the application examples of such a driving device is an image blur correction mechanism mounted on an imaging device. In the image blur correction mechanism, an imaging element (image sensor) or an image blur correction lens is mounted on a movable unit, and based on the camera shake amount detected by a predetermined sensor, the movable unit is driven so as to eliminate image blur.

[0004] In an image blur correction mechanism adopting a VCM method, contact resistance can be reduced and smooth driving can be performed by generally arranging a plurality of balls rollably between a movable unit and a fixed unit. In this case, as a method of sandwiching the balls between the movable unit and the fixed unit so that the balls can reliably contact the movable unit and the fixed unit, a method of pulling the movable unit and the fixed unit closer to each other with a spring and a magnet is used (see Japanese Patent Nos. 6511495 and 6719056).

[0005] For example, when shooting with a camera while walking, the camera shake becomes larger, so an image blur correction device capable of eliminating such large camera shake is required. By increasing the movement of the movable unit relative to the fixed unit, the image blur correction device of the camera can correct a larger camera shake.

[0006] In order to solve such a problem, the technology described in Japanese Patent No. 6511495 and Patent No. 6719056 has a structure in which a magnet and a magnetic body are used as a means for pulling the movable unit and the fixed unit closer to each other, but as the amount of movement (movement distance) increases, a return force to the center is generated due to the magnetic force. This return force can quickly return to the state where the image blur correction is not performed, but on the other hand, there is a problem that this return force increases the driving load when the image blur correction is performed. Summary of the invention

[0007] The present invention provides a driving device, an image blur correction device, an imaging apparatus, and a lens barrel, which reduces a return force to a center and suppresses a load on an actuator driving a movable unit when a movable unit is moved relative to a fixed unit.

[0008] Therefore, the present invention provides a driving device, which includes: a fixed unit; a movable unit, which is arranged to be able to move relative to the fixed unit within a predetermined range in a plane; a plurality of rolling members, which are arranged between the fixed unit and the movable unit; an actuator, which is configured to drive the movable unit; and a force-applying unit, which is configured to apply force to the movable unit toward the fixed unit via the rolling members, wherein the force-applying unit includes a magnet and a magnetic body, one of the magnet and the magnetic body is held by the movable unit, and the other of the magnet and the magnetic body is held by the fixed unit, and when viewed from a direction orthogonal to the plane, the range in which the magnet can move when the actuator is driven to move the movable unit does not protrude from the end of the magnetic body.

[0009] According to the present invention, when the movable unit is moved relative to the fixed unit, the returning force to the center can be reduced, and the load on the actuator driving the movable unit can be suppressed.

[0010] Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a diagram showing a schematic configuration of an image pickup apparatus according to an embodiment of the present invention.

[0012] Figure 2 It is an exploded perspective view of a first image blur correction unit provided in the imaging apparatus.

[0013] Figure 3 is another exploded perspective view of the first image blur correction unit provided in the imaging apparatus.

[0014] Figure 4 It is an exploded perspective view of a movable unit constituting a first image blur correction unit.

[0015] Figure 5 is another exploded perspective view of the movable unit constituting the first image blur correction unit.

[0016] Fig. 6A This is the first projection of the force unit consisting of the back yoke and the thrust magnet in the direction of the optical axis. Figure 6B This is a first cross-sectional view of the force applying unit consisting of the back yoke and the thrust magnet.

[0017] Fig. 7A This is the second projection of the force unit composed of the back yoke and the thrust magnet in the direction of the optical axis. Figure 7B This is a second cross-sectional view of the force applying unit consisting of the back yoke and the thrust magnet.

[0018] Fig. 8A and Figure 8C is the projection of the actuator in the direction of the optical axis, Figure 8B and Fig.8D is a cross-sectional view of the actuator.

[0019] Fig. 9 It is a projection diagram of the first image blur correction unit in the optical axis direction when the power of the main body of the imaging apparatus is not turned on.

[0020] Fig. 10A is a front view of a movable unit constituting a first image blur correction unit, Fig. 10B is a cross-sectional view of a movable unit constituting a first image blur correction unit.

[0021] Fig.11A is a front view of the first image blur correction unit, Fig. 11B is a cross-sectional view of a first image blur correction unit.

[0022] Fig.12 yes Fig. 11B A partial enlarged view of the cross-sectional view.

[0023] Fig.13 : is a graph showing the temperature-strength characteristics of the first bonding part and the second bonding part. DETAILED DESCRIPTION

[0024] The present invention will be described in detail below with reference to the accompanying drawings showing embodiments of the present invention.

[0025] Here, although a configuration in which the driving device according to the present invention is applied to an image blur correction device of an imaging apparatus will be described as one of application examples of the driving device according to the present invention, application examples of the driving device according to the present invention are not limited to imaging apparatuses.

[0026] Figure 1 1 is a diagram showing a schematic configuration of an image pickup apparatus 10 according to an embodiment of the present invention. The image pickup apparatus 10 is a so-called mirrorless SLR digital camera (i.e., a mirrorless interchangeable lens digital camera), and has an image pickup apparatus body 10a (hereinafter simply referred to as "body 10a") and a lens barrel 10b that can be attached to / detached from the body 10a.

[0027] The main body 10a includes an image pickup element (image sensor) 11 having an image pickup surface 11a, a base member 13c, a main body side mounting member 13a, a camera control unit 14, a first image blur correction control unit 15a, a first vibration detection unit 16a, an image processing unit 17, and a first image blur correction unit 20. In addition, the lens barrel 10b includes an image pickup optical system 12 including an image blur correction lens 12b, a lens side mounting member 13b, a second image blur correction control unit 15b, a second vibration detection unit 16b, and a second image blur correction unit 60.

[0028] The imaginary light ray representing the light beam irradiated to the imaging surface 11a of the imaging element 11 via the imaging optical system 12 is referred to as the "imaging optical axis 12a" (hereinafter referred to as the "optical axis 12a"). In addition, the plane orthogonal to the optical axis 12a is referred to as the "optical axis orthogonal plane" (hereinafter referred to as the "optical axis orthogonal plane 12c"). The optical axis 12a passes through the center of the imaging surface 11a and is orthogonal to the imaging surface 11a. In addition, in order to clarify the arrangement and positional relationship of each part (each structural element) constituting the imaging device 10 within the imaging device 10, as shown in FIG. Figure 1 As shown in FIG. 1 , mutually orthogonal X, Y, and Z directions are defined. The Z direction is a direction parallel to the optical axis 12a, the X direction is a width direction of the imaging device 10, and the Y direction is a height direction of the imaging device 10. When both the X direction and the Z direction are in a horizontal plane, the Y direction becomes a vertical direction. Therefore, the optical axis orthogonal plane 12c becomes an XY plane.

[0029] The imaging element 11 is composed of a photoelectric conversion element such as a CMOS (Complementary Metal Oxide Semiconductor) image sensor or a CCD (Charge Coupled Device) image sensor, and is arranged so that the imaging surface 11a faces the subject side (the barrel 10b side) and the imaging surface 11a is orthogonal to the optical axis 12a. The imaging element 11 generates an image signal by photoelectrically converting the optical image of the subject formed on the imaging surface 11a by the imaging optical system 12. The image signal generated by the imaging element 11 is converted into image data by the image processing unit 17 that performs various processes, and the image data is stored in a memory (storage device) (not shown). The camera control unit 14 is a computing component within a main IC (Integrated Circuit) (not shown), receives input operations from a user via an operating component (not shown), and controls the overall operation of the imaging device 10.

[0030] The imaging optical system 12 is composed of a lens group (not shown) arranged in the lens barrel 10b, and forms an optical image on the imaging surface 11a of the imaging element 11 by the reflected light from the subject (not shown). In the imaging device 10, in order to arrange the imaging element 11 with high positional accuracy relative to the optical axis 12a, the imaging element 11 is mounted to a base member 13c provided in the main body 10a, and the lens barrel 10b is also connected to the base member 13c. In this case, the imaging element 11 is mounted to the base member 13c via the first image blur correction unit 20. In addition, the lens barrel 10b is connected to the base member 13c via the lens side mounting member 13b and the main body side mounting member 13a.

[0031] The first image blur correction unit 20 corrects the image blur caused by camera shake generated in the imaging device 10 by moving the imaging element 11 in the optical axis orthogonal direction or rotating the imaging element 11 within the optical axis orthogonal plane 12c, and makes it possible to obtain a clear subject image. Specifically, when the posture of the imaging device 10 relative to the subject changes during imaging, the image obtained by the imaging element 11 is blurred because the imaging position of the subject light beam on the imaging plane 11a of the imaging element 11 changes. At this time, in the case where the posture change of the imaging device 10 is sufficiently small, the change in the imaging position is uniform within the imaging plane 11a, and can be regarded as a translation or rotation movement (image plane blur) within the optical axis orthogonal plane 12c. Therefore, by moving the imaging element 11 translationally or rotationally within the optical axis orthogonal plane 12c so as to eliminate the image plane blur, a clear subject image with the image blur corrected can be obtained. Furthermore, the first image blur correction unit 20 may be configured to move the imaging element 11 in a direction orthogonal to the imaging surface when moving the imaging element 11 in a direction parallel to the imaging surface.

[0032] Likewise, the second image blur correction unit 60 corrects the image blur caused by the camera shake generated in the image pickup device 10 by moving the image blur correction lens 12b in the direction orthogonal to the optical axis or rotating the image blur correction lens 12b in the plane 12c orthogonal to the optical axis, and makes it possible to obtain a clear subject image. That is, the optical axis 12a is adjusted by moving the image blur correction lens 12b in the direction orthogonal to the optical axis. At this time, the image blur correction lens 12b moves in the direction orthogonal to the optical axis, thereby eliminating the image plane blur. As a result, a clear subject image corrected for image blur can be obtained. In addition, since the principle of image blur correction by moving the image pickup element 11 or the image blur correction lens 12b is well known, a more detailed description will be omitted. In addition, the second image blur correction unit 60 may be configured to move the image blur correction lens 12b in the optical axis direction when the image blur correction lens 12b is moved in the direction orthogonal to the optical axis.

[0033] The first image blur correction unit 20 schematically includes a fixed unit, a movable unit, and a plurality of driving force generating units. The fixed unit is fixed to the base member 13c, and the movable unit holds the image pickup element 11. In addition, the movable unit is supported by the fixed unit with three degrees of freedom, and can be relatively moved relative to the fixed portion in the direction orthogonal to the optical axis and relatively rotated within the plane orthogonal to the optical axis 12c. That is, the first image blur correction unit 20 is configured as a driving device (so-called XY-θ stage) capable of three-axis drive control, and can move the image pickup element 11 in the direction orthogonal to the optical axis and rotate the image pickup element 11 within the plane orthogonal to the optical axis 12c.

[0034] The second image blur correction unit 60 schematically has a fixed unit, a movable unit, and a plurality of driving force generating units. The fixed unit is fixed to a housing (not shown) of the lens barrel 10b, and the movable unit holds the image blur correction lens 12b. In addition, the movable unit is supported by the fixed unit with two degrees of freedom, and can move relative to the fixed portion in a direction orthogonal to the optical axis. That is, the second image blur correction unit 60 is configured as a driving device (so-called XY stage) capable of biaxial drive control, and can move the image blur correction lens 12b in a direction orthogonal to the optical axis.

[0035] The first vibration detection unit 16a and the second vibration detection unit 16b are respectively constituted by a gyro sensor, an acceleration sensor, etc., and are camera shake detection means that detect angular velocity, acceleration, etc. in various directions of the imaging device 10 as camera shake information of the imaging device 10. The first image blur correction control unit 15a and the second image blur correction control unit 15b respectively integrate the angular velocity and acceleration detected by the first vibration detection unit 16a and the second vibration detection unit 16b to calculate the angular change amount and the movement amount in various directions of the imaging device 10 as camera shake information. That is, the first vibration detection unit 16a, the second vibration detection unit 16b, the first image blur correction control unit 15a, and the second image blur correction control unit 15b function as a first detection unit that detects the camera shake information of the fixed unit. In addition, the first image blur correction control unit 15a calculates the movement target value of the imaging element 11 based on the camera shake information detected by the first vibration detection unit 16a, and controls the driving of the first image blur correction unit 20 to control the movement of the imaging element 11. Likewise, the second image blur correction control unit 15b calculates a movement target value of the image blur correction lens 12b based on the camera shake information detected by the second vibration detection unit 16b, and controls driving of the second image blur correction unit 60 so as to control movement of the image blur correction lens 12b.

[0036] Furthermore, the imaging apparatus 10 may be configured to include only one of the first image blur correction unit 20 and the second image blur correction unit 60. In the case where the imaging apparatus 10 does not include the first image blur correction unit 20, the imaging element 11 is fixedly arranged relative to the optical axis 12a. Furthermore, in the case where the imaging apparatus 10 does not include the second image blur correction unit 60, the image blur correction lens 12b is basically unnecessary. That is, the imaging optical system 12 of the lens barrel 10b is designed so that desired optical characteristics can be obtained by a lens configuration that does not include the image blur correction lens 12b.

[0037] Next, a detailed configuration of the first image blur correction unit 20 will be described. In addition, since the configuration of the second image blur correction unit 60 is similar to that of the first image blur correction unit 20, a description thereof will be omitted.

[0038] Figure 2 and Figure 3 is an exploded perspective view of the first image blur correction unit 20, and Figure 2 The direction for observing the first image blur correction unit 20 is different from Figure 3 The first image blur correction unit 20 includes a fixed unit 20a and a movable unit 20b (movable member). Figure 2 and Figure 3 In the figure, the movable unit 20b is shown in an unexploded manner, and the fixed unit 20a is shown in an exploded manner.

[0039] The fixing unit 20a has a fixing member 21, a back yoke 22, a first back magnet group 23a, a second back magnet group 23b, and a third back magnet group 23c. The fixing member 21 is provided with a first opening 21a, a second opening 21b, and a third opening 21c. The first back magnet group 23a, the second back magnet group 23b, and the third back magnet group 23c are respectively fixed to the back yoke 22 by means of an adhesive or the like, and are arranged to be surrounded by the first opening 21a, the second opening 21b, and the third opening 21c.

[0040] In the present embodiment, two magnets are used as the first rear magnet group 23a, the second rear magnet group 23b, and the third rear magnet group 23c, respectively, and the two magnets are arranged in parallel so that the two magnets magnetized in the optical axis direction (Z direction) generate magnetic fields in opposite directions to each other. However, the first rear magnet group 23a, the second rear magnet group 23b, and the third rear magnet group 23c are not limited to such two magnets, and a single magnet magnetized at two poles may be used.

[0041] The fixing unit 20a further includes a first column member 24a, a second column member 24b, a third column member 24c, a front yoke 25, a first front magnet 26a, a second front magnet 26b, and a third front magnet 26c. The front yoke 25 is fixed to the fixing member 21 via the first column member 24a, the second column member 24b, and the third column member 24c by means of screws. The first front magnet 26a, the second front magnet 26b, and the third front magnet 26c are respectively fixed to the front yoke 25 by means of an adhesive or the like.

[0042] In the present embodiment, one magnet magnetized with two poles is used as the first front magnet 26a, the second front magnet 26b, and the third front magnet 26c, respectively. However, the first front magnet 26a, the second front magnet 26b, and the third front magnet 26c are not limited to such one magnet, and two magnets may be used, which are arranged in parallel so that the two magnets magnetized in the optical axis direction generate magnetic fields in opposite directions to each other.

[0043] The first rear magnet group 23a and the first front magnet 26a arranged in parallel along the optical axis form a first magnetic circuit. Similarly, the second rear magnet group 23b and the second front magnet 26b form a second magnetic circuit, and the third rear magnet group 23c and the third front magnet 26c form a third magnetic circuit.

[0044] The fixed unit 20a also has a first limiting member 28, a second limiting member 29 and a cover 30. The back yoke 22 has a first limiting portion 22a, and the front yoke 25 has a second limiting portion 25a. The movement of the movable unit 20b is limited within a predetermined range within the optical axis orthogonal plane 12c by the first limiting member 28, the second limiting member 29, the first limiting portion 22a, the second limiting portion 25a, the first column member 24a, the second column member 24b and the third column member 24c. A cushioning material such as rubber that absorbs impact when abutting is provided at the abutting portion of these members and parts that limit the movement of the movable unit 20b, so as to avoid damage and reduce impact noise. The cover 30 prevents contact between the back yoke 22 and a flexible printed circuit board such as a drive FPC (flexible printed circuit) 35 to be described later.

[0045] Figure 4 and Figure 5 is an exploded perspective view of the movable unit 20b, and Figure 4 The direction of the observation movable unit 20b in Figure 5The direction of observation of the movable unit 20b is different. The movable unit 20b has an imaging element holding member 31 and an imaging element 11. The imaging element 11 is fixed to the imaging element holding member 31 by means of an adhesive or the like, the details of which will be described later. In addition, the movable unit 20b has a mask 32a, an infrared absorption filter 32b, an optical low-pass filter 32c, and a vibration unit 32f. The mask 32a, the infrared absorption filter 32b, and the optical low-pass filter 32c are held by a holding member 32d and a holding metal sheet 32e, and are fixed to the imaging element 11 by an adhesive member or the like. The mask 32a prevents unnecessary light from outside the imaging optical path from entering the imaging element 11. The optical low-pass filter 32c reduces moire caused by the repetitive pattern of the subject. The vibration unit 32f is provided in the optical low-pass filter 32c, and removes foreign matter such as dust attached to the surface of the optical low-pass filter 32c by vibrating the optical low-pass filter 32c. In addition, since the principle and control of removing foreign matter by the vibration unit 32f are well known, a detailed description thereof will be omitted.

[0046] The movable unit 20b further includes a first coil 33a, a second coil 33b, a third coil 33c and a driving FPC 35. The driving FPC 35 is arranged to overlap with the first coil 33a, the second coil 33b, and the third coil 33c on the optical axis projection plane (i.e., the XY plane when viewed from the Z direction), and is fixed to the imaging element holding member 31 by means of an adhesive or the like.

[0047] The imaging element holding member 31 has a first recess 31a, a second recess 31b, and a third recess 31c. The first coil 33a is arranged inside the first recess 31a, the second coil 33b is arranged inside the second recess 31b, and the third coil 33c is arranged inside the third recess 31c, and the first coil 33a, the second coil 33b, and the third coil 33c are fixed to the imaging element holding member 31 by means of an adhesive or the like.

[0048] The first magnetic circuit and the first coil 33a form a VCM as a first actuator, the second magnetic circuit and the second coil 33b form a VCM as a second actuator, and the third magnetic circuit and the third coil 33c form a VCM as a third actuator. The Lorentz force is generated in a direction orthogonal to the magnetic field generated in the first magnetic circuit along the optical axis direction and the current flowing in the first coil 33a, and the resultant direction of the Lorentz force changes according to the energization direction of the first coil 33a. The same Lorentz force is generated in the second magnetic circuit and the second coil 33b and in the third magnetic circuit and the third coil 33c. The first actuator and the second actuator generate respective forces (respective driving forces) roughly parallel to the X direction, the translational force in the X direction is generated by the sum of the respective forces, and the rotational force around the optical axis is generated by the difference between the respective forces. The third actuator generates a translational force in the Y direction.

[0049] The first detector 35a, the second detector 35b and the third detector 35c are mounted to the driving FPC 35. The first detector 35a is arranged inside the first coil 33a, the second detector 35b is arranged inside the second coil 33b, and the third detector 35c is arranged inside the third coil 33c. The first detector 35a, the second detector 35b and the third detector 35c are, for example, Hall elements. The first detector 35a detects the magnetic force of the first magnetic circuit. Based on the detection result of the first detector 35a, the first image blur correction control unit 15a calculates the position information (specifically, the position and angle around the optical axis) of the movable unit 20b relative to the fixed unit 20a in the optical axis orthogonal plane 12c. The same applies to the second detector 35b and the third detector 35c. That is, the first detector 35a, the second detector 35b, the third detector 35c and the first image blur correction control unit 15a play the role of a second detection unit that detects the relative position information of the movable unit relative to the fixed unit. The first coil 33a, the second coil 33b, and the third coil 33c are electrically connected to the driving FPC 35, and the first image blur correction control unit 15a controls the current flowing through each coil via the driving FPC 35. That is, the first image blur correction control unit 15a, which functions as a control unit, controls the driving of the movable unit 20b by feedback control based on the deviation between the moving target value of the imaging element 11 based on the camera shake information detected by the first vibration detection unit 16a and the current position of the imaging element 11 detected by the Hall element.

[0050] The movable unit 20b is moved by the attraction force generated between the back yoke 22 and the thrust magnet 39 via the ball 36 (see FIG. Figure 2 and Figure 3 ) applies force to the fixed member 21 constituting the fixed unit 20a. In other words, the back yoke 22 and the thrust magnet 39 constitute a force applying unit that causes the movable unit 20b to apply force to the fixed unit 20a. In addition, in order to generate an attractive force between the back yoke 22 and the thrust magnet 39, the back yoke 22 needs to be a magnetic body (a member made of a magnetic material). The details of the force applying unit will be described later.

[0051] The balls 36 are arranged in the first enclosure 31d, the second enclosure 31e, and the third enclosure 31f provided on the image pickup element holding member 31, respectively. Since the balls 36 roll when the movable unit 20b moves relative to the fixed unit 20a in the optical axis orthogonal plane 12c, the load generated by the friction between the balls and the image pickup element holding member 31 and the fixed member 21 hardly occurs. In addition, the movement of the movable unit 20b in the direction opposite to the direction in which the force applying unit composed of the rear yoke 22 and the thrust magnet 39 applies force to the movable unit 20b is restricted by the front yoke 25 and the first restricting member 28. Therefore, even if an impact is applied to the image pickup apparatus 10 and an external force such as pulling the movable unit 20b away from the fixed member 21 is applied, the movable unit 20b will not fall off from the fixed unit 20a.

[0052] The movable unit 20b includes a connecting member 38 that bridges the opening of the image pickup element holding member 31 and is fixed to the image pickup element holding member 31 on both sides of the optical axis by means of screws 45. The abutment portion 38a is provided in two positions of the connecting member 38, and when the abutment portion 38a abuts on the first limiting portion 22a of the back yoke 22, the movement of the movable unit 20b in the optical axis orthogonal plane 12c is limited to a certain range.

[0053] The thrust magnet 39 and the thrust yoke 40 are fixed to the connecting member 38 by means of an adhesive or the like, and the thrust magnet 39 is magnetized in the optical axis direction. In addition, as the thrust magnet 39, a magnet magnetized with two poles so that magnetic fields in different directions are arranged in the Y direction can be used, but a magnet magnetized with a single pole can also be used.

[0054] The force applying unit composed of the back yoke 22 and the thrust magnet 39 is arranged inside the triangle formed by the three balls 36, which are arranged inside the first enclosure 31d, the second enclosure 31e and the third enclosure 31f, respectively. As a result, a balanced force can be generated for each ball 36.

[0055] Next, the urging unit composed of the back yoke 22 and the thrust magnet 39 will be described in detail. Fig. 6A and Fig. 7A 2 are projection diagrams of the force applying unit composed of the back yoke 22 and the thrust magnet 39 in the optical axis direction when viewed from the subject side. Specifically, Fig. 6A An example of a state in which the movable unit 20b is within the image stabilization control range of the first image blur correction unit 20 performed by the first image blur correction control unit 15a is represented by the position of the thrust magnet 39 relative to the back yoke 22. Fig. 7AOne example of a state in which the movable unit 20 b protrudes outside the image stabilization control range of the first image blur correction unit 20 performed by the first image blur correction control unit 15 a is represented by the position of the thrust magnet 39 relative to the back yoke 22 . Figure 6B It is along Fig. 6A The cross-sectional view is taken along the arrow AA shown. Figure 7B It is along Fig. 7A The cross-sectional view is taken along arrow BB.

[0056] Since the thrust magnet 39 is fixed to the connecting member 38 constituting the movable unit 20b, the thrust magnet 39 moves relatively with respect to the back yoke 22 as the movable unit 20b moves. Fig. 6A , a region (range) in which the thrust magnet 39 can move according to the image stabilization control range of the first image blur correction unit 20 is indicated by a dotted line as a movable region 41 .

[0057] like Fig. 6A and Figure 6B As shown in FIG. 1 , the movable region 41 of the thrust magnet 39 does not protrude from the end surface of the back yoke 22 on the optical axis projection plane. Therefore, the force of the force applying unit acts only in the optical axis direction and does not act in the direction orthogonal to the optical axis 12a. As a result, the force applying unit does not reduce the image stabilization controllability of the first image blur correction unit 20 (i.e., the driving controllability of the movable unit 20b). In addition, as Figure 7B As shown, in the case where the thrust magnet 39 protrudes from the end of the rear yoke 22 on the optical axis projection plane, although part of the force of the force unit acts in a direction orthogonal to the optical axis 12a, it does not affect the driving controllability of the movable unit 20b because it is outside the image stabilization control range.

[0058] As described above, in a case where the amount of movement of the movable unit 20b from the reference position of the movable unit 20b relative to the back yoke 22 is greater than a predetermined value, a part of the attractive force generated between the thrust magnet 39 and the back yoke 22 is used as a force in the direction of returning the movable unit 20b to the reference position. On the other hand, in a case where the amount of movement of the movable unit 20b from the reference position of the movable unit 20b relative to the back yoke 22 is not greater than a predetermined value, the attractive force generated between the thrust magnet 39 and the back yoke 22 is not used as a force in the direction of returning the movable unit 20b to the reference position.

[0059] Subsequently, the driving force of the first actuator, the driving force of the second actuator, and the driving force of the third actuator when the movable unit 20 b largely moves within the optical axis orthogonal plane 12 c will be described. Fig. 8A and Figure 8C 1 and 2 are projection diagrams of the actuator 34 in the optical axis direction when viewed from the subject side. Figure 8B It is along Fig. 8AThe cross-sectional view is taken along the arrow CC shown. Fig.8D It is along Figure 8C A cross-sectional view taken along arrow DD is shown.

[0060] In addition, since the first actuator, the second actuator, and the third actuator have different driving force generation directions but the same function, they are referred to as "actuator 34". Similarly, since the first coil 33a, the second coil 33b, and the third coil 33c have the same function, they are referred to as "coil 33". In addition, the first rear magnet group 23a, the second rear magnet group 23b, and the third rear magnet group 23c that are opposite to the first coil 33a, the second coil 33b, and the third coil 33c in the optical axis direction are also referred to as "magnets 23".

[0061] When the movable unit 20b moves relative to the fixed unit 20a, the coil 33 constituting the actuator 34 moves relative to the magnet 23. Therefore, when the movable unit 20b moves greatly relative to the fixed unit 20a, the coil 33 also moves relatively greatly relative to the magnet 23.

[0062] exist Fig. 8A In the state shown, the movable unit 20b moves within the plane 12c perpendicular to the optical axis to a position where one side of the coil 33 faces the magnetization switch mb of the magnet 23. Fig. 8A The state of further significant movement Figure 8C In the state shown, one side of the coil 33 is not opposed to the magnet 23. In these cases, the return force of the actuator 34 which attempts to return the movable unit 20b to the initial position (position (reference position) where the camera shake correction amount becomes zero) is reduced.

[0063] However, after the movable unit 20b has moved substantially to Fig. 7A and Figure 7B In the state where the thrust magnet 39 is shown protruding from the end of the back yoke 22 in the optical axis orthogonal plane 12c, the component of the attractive force generated by the force applying unit in the direction orthogonal to the optical axis 12a assists the return force for returning the movable unit 20b to the initial position. In this way, in the first image blur correction control unit 15a, a sufficiently large return force for returning the movable unit 20b to the initial position can be obtained without increasing the size of the actuator 34 or increasing the current flowing through the coil 33.

[0064] Next, the relationship between the attractive force generated by the force applying unit, which assists the thrust (driving force) of the actuator 34 when returning the movable unit 20 b to the initial position, and the gravity will be described. Fig. 91 is a projection diagram of the first image blur correction unit 20 in the optical axis direction when the power source in the main body 10a is not turned on when viewed from the subject side. Fig. 9 , the cover 30 provided in the first image blur correction unit 20 is not shown.

[0065] In a state where the power supply of the imaging apparatus 10, which also functions as a energizing unit for passing current through the coil, is not turned on, the user generally places the imaging apparatus 10 on a table or the like in such a manner that the Y direction becomes the gravity direction (i.e., the ZX plane becomes parallel to the horizontal direction). In this case, since the first coil 33a, the second coil 33b, and the third coil 33c are not energized, as shown in FIG. Fig. 9 As shown, the movable unit 20b moves in the Y direction due to gravity.

[0066] As described above, the connection member 38 of the movable unit 20b has two abutting portions 38a. Here, the position where one of the two abutting portions 38a close to the center of gravity 42 of the movable unit 20b abuts on the first limiting portion 22a is defined as the abutting position 43. At this time, in the optical axis orthogonal plane 12c, a first moment 44a caused by gravity centered on the abutting position 43 and a second moment 44b caused by the return force of the force applying unit are generated. Since the second moment 44b caused by the return force of the force applying unit is smaller than the first moment 44a caused by gravity, the movable unit 20b is maintained in a state where the two abutting portions 38a abut on the first limiting portion 22a due to the balance with gravity. As a result, since the imaging element 11 does not tilt in the optical axis orthogonal plane 12c, the performance of the imaging device 10 is not impaired.

[0067] Next, we will refer to Fig. 10A , Fig. 10B , Fig.11A and Fig. 11B The structure of bonding the image pickup element 11 to the image pickup element holding member 31 so as to hold the image pickup element 11 is described. In order to improve the image quality of the image pickup device 10, it is desirable to improve the position accuracy of the image pickup element 11. In addition, in consideration of the use of the image pickup device 10, it is desirable to improve the impact resistance in various situations. In order to meet such requirements, the image pickup element 11 is bonded to the image pickup element holding member 31 by the following reference Fig. 10A and Fig. 10B The first adhesive portion 51 described below and the Fig.11A and Fig. 11B The illustrated second adhesive portion 52 is fixed to the image pickup element holding member 31 .

[0068] Fig. 10A is a diagram (front view) of the movable unit 20b when viewed from the subject side, Fig. 10B It is along Fig. 10AEE shown in the figure is a cross-sectional view. The inner peripheral portion 31g of the imaging element holding member 31 and the back surface portion 11b of the imaging element 11 are bonded to each other through the first bonding portion 51, and the imaging element 11 is held by the imaging element holding member 31. The first bonding portion 51 is formed by curing the first adhesive, and an ultraviolet curing resin or the like is used as the first adhesive. By applying a liquid ultraviolet curing resin to the bonding portion and irradiating it with ultraviolet rays, the ultraviolet curing resin is chemically converted into a solid. At this time, the imaging element holding member 31 and the first adhesive are bonded and the first adhesive and the imaging element 11 are bonded to each other to form the first bonding portion 51, and the imaging element 11 is bonded and fixed to the imaging element holding member 31.

[0069] Furthermore, as described above, the connecting member 38 is fastened to the image pickup element holding member 31 by the screw 45. If the image pickup element 11 is fixed to the image pickup element holding member 31 by the first adhesive portion 51 and the second adhesive portion 52, and then the connecting member 38 is attached to the image pickup element holding member 31 by the screw 45, there is a possibility that the image pickup element holding member 31 is slightly deformed due to the stress caused by the tightening torque of the screw 45. As a result, there is a concern that positional displacement of the image pickup element 11 may occur.

[0070] To avoid this problem, in this embodiment, Fig. 10A As shown, the first adhesive portion 51 is formed by applying the first adhesive to the upper and lower sides of the imaging element 11 and curing the first adhesive. As a result, a structure can be obtained in which the connecting member 38 extending in the left-right direction relative to the imaging element holding member 31 does not overlap with the first adhesive portion 51 when viewed from the optical axis direction (the direction orthogonal to the imaging surface 11a of the imaging element 11). As a result, since the first adhesive can be applied and cured after the connecting member 38 is attached to the imaging element holding member 31 by the screw 45, the positional deviation of the imaging element 11 can be suppressed and the positional accuracy of the imaging element 11 can be improved. In addition, by bonding in a pair of regions (a pair of regions along each side) sandwiching the center of the imaging element 11, the imaging element 11 can be stably fixed to the imaging element holding member 31.

[0071] Fig.11A This is a diagram (front view) of the first image blur correction unit 20 when viewed from the subject side. Fig. 11B It is along Fig.11A The cross-sectional view is taken along the arrow FF shown. Fig.12 yes Fig. 11B5 is an enlarged view of the region 55 in FIG. From the viewpoint of improving the impact resistance of the imaging device 10, it is desirable to firmly fix the imaging element 11 to the imaging element holding member 31. Therefore, in the imaging device 10, in addition to the first adhesive portion 51, the imaging element 11 is adhesively fixed to the imaging element holding member 31 by the second adhesive portion 52.

[0072] As the second adhesive forming the second adhesive portion 52, an ultraviolet curable resin or the like can be used, as the first adhesive forming the first adhesive portion 51. Fig.11A As shown in FIG. 1 , the second adhesive is applied to the left and right sides of the image pickup element 11. Fig.12 As shown, after applying the second adhesive between the side wall portion 31 h of the imaging element holding member 31 and the side surface portion 11 c of the imaging element 11 , the second adhesive portion 52 is formed by curing the second adhesive, and the imaging element 11 is bonded and fixed to the imaging element holding member 31 .

[0073] Thus, in the image pickup device 10, the first adhesive portion 51 adheres the upper and lower sides of the image pickup element 11, the second adhesive portion 52 adheres the left and right sides of the image pickup element 11, and the first adhesive portion 51 and the second adhesive portion 52 are arranged so as not to overlap each other when viewed from the optical axis direction. In addition, the back surface portion 11b of the image pickup element 11 is adhered by the first adhesive portion 51, and the side surface portion 11c of the image pickup element 11 is adhered by the second adhesive portion 52. By adopting such a configuration, even if an impact (external force) is applied to the image pickup device 10 from various directions, the position of the image pickup element 11 relative to the image pickup element holding member 31 can be maintained with high accuracy.

[0074] Next, the difference between the first adhesive portion 51 and the second adhesive portion 52 will be described. The first adhesive portion 51 adheres the imaging element 11 to the imaging element holding member 31 over a wide range in a manner that covers the back side portion 11b of the imaging element 11 and the inner peripheral portion 31g of the imaging element holding member 31. Therefore, in the case of using a low-viscosity adhesive as the first adhesive, there is a possibility that when the first adhesive is applied, the coverage on the inner peripheral portion 31g may become shallow due to the first adhesive spreading on the back side portion 11b. Therefore, it is desirable to adopt a high-viscosity adhesive for the first adhesive portion 51 so as to cover both the back side portion 11b and the inner peripheral portion 31g.

[0075] On the other hand, as described above, the second adhesive portion 52 is formed between the side wall portion 31h of the imaging element holding member 31 and the side surface portion 11c of the imaging element 11. Fig.12As shown, in order to ensure the movable area of ​​the movable unit 20b, it is necessary to provide a gap X1 between the movable unit 20b and the fixed unit 20a. In addition, in order to hold the imaging element 11 by the side portion, it is necessary to provide a space for applying the second adhesive and a width X2 which is the thickness of the side wall portion 31h of the imaging element holding member 31 inside the imaging element 11. In order to reduce the size of the first image blur correction unit 20, it is desirable to reduce the width X2, and in consideration of pouring the adhesive into such a narrow area, it is desirable to use an adhesive having a low viscosity as the second adhesive.

[0076] As described above, it is desirable to use an adhesive having a viscosity lower than that of the first adhesive as the second adhesive. In addition, since the coating range of the first adhesive is larger than that of the second adhesive, it is desirable to set the first adhesive portion 51 as the main adhesive portion and the second adhesive portion 52 as the secondary adhesive portion.

[0077] In addition, since it is expected that the imaging device 10 is used in various temperature environments, it is desirable that high impact resistance can be obtained even in various temperature environments. Here, considering that the adhesive strength of the adhesive has temperature dependence, it is desirable to combine adhesives having different temperature characteristics in terms of adhesive strength in the first adhesive portion 51 and the second adhesive portion 52.

[0078] Fig.13 1 is a diagram for explaining an example of selecting the first adhesive portion 51 and the second adhesive portion 52 in consideration of the temperature characteristics of the adhesive strength (adhesive strength-temperature characteristics). Fig.13 In the graph, the horizontal axis represents temperature T, the vertical axis represents adhesive strength P, and curve P51 shows the temperature-adhesive strength characteristics of the first adhesive portion 51, and curve P52 shows the temperature-adhesive strength characteristics of the second adhesive portion 52. In addition, the solid line P51+P52 shows the sum of the curves P51 and P52, that is, the solid line P51+P52 shows the temperature characteristics of the overall adhesive strength of the imaging element 11 with respect to the imaging element holding member 31.

[0079] like Fig.13 As shown, by combining the first adhesive portion 51 on the high temperature resistant side and the second adhesive portion 52 on the low temperature resistant side, a mechanism for holding the image pickup element 11 having high impact resistance can be realized in a wide temperature range. In addition, when the image pickup device 10 is used, the temperature near the image pickup element 11 tends to rise due to the influence of heat generation of the image pickup element 11, so it is desirable to use an adhesive that exhibits high adhesive strength on the high temperature side for the first adhesive portion 51 as the main adhesive portion.

[0080] Although the present invention is described in detail based on the preferred embodiments of the present invention, the present invention is not limited to these specific embodiments, and various embodiments within the scope of the gist of the present invention are also included in the present invention. In addition, each of the above-mentioned embodiments is only an embodiment of the present invention, and each embodiment can be appropriately combined.

[0081] For example, with respect to the magnet and the coil constituting the VCM as the actuator, one of the magnet and the coil may be arranged in the fixed unit, and the other of the magnet and the coil may be arranged in the movable unit. In addition, with respect to the thrust magnet and the back yoke constituting the force applying unit, one of the thrust magnet and the back yoke may be arranged in the fixed unit, and the other of the thrust magnet and the back yoke may be arranged in the movable unit.

[0082] In addition, in the case where the connecting member is arranged to extend in the up-down direction, the first adhesive portion may be arranged on the left and right sides of the imaging element (the first adhesive may be applied to the left and right sides of the imaging element), and the second adhesive portion may be arranged on the upper and lower sides of the imaging element (the second adhesive may be applied to the upper and lower sides of the imaging element). In addition, in the case where the imaging element holding member forms three sides when viewed from the optical axis direction and the connecting member is attached to the remaining side so that an opening is formed, the first adhesive may be applied to a position that does not overlap with the connecting member when viewed from the optical axis direction.

[0083] While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

[0084] This application claims priority from Japanese Patent Application No. 2021-021830 filed on February 15, 2021, and Japanese Patent Application No. 2021-076427 filed on April 28, 2021, which are hereby incorporated by reference in their entirety.

Claims

1. A driving device, comprising: Fixed components; a movable member arranged to be relatively movable within a predetermined range within a plane relative to the fixed member; a plurality of rolling members disposed between the fixed member and the movable member; an actuator configured to drive the movable member; and a force applying unit, which is configured to include a magnet and a magnetic body and to apply force to the movable member toward the fixed member via the rolling member, The invention is characterized in that one of the magnet and the magnetic body is held by the movable member, and the other of the magnet and the magnetic body is held by the fixed member, and When viewed from a direction orthogonal to the plane, a range in which the magnet can move when the actuator is driven to move the movable member does not protrude from an end portion of the magnetic body.

2. The driving device according to claim 1, in, When the magnet protrudes from the end of the magnetic body when viewed from a direction perpendicular to the plane, the force applied by the force applying unit in the direction parallel to the plane is greater than the force applied by the force applying unit in the direction parallel to the plane when the magnet does not protrude from the end of the magnetic body.

3. The driving device according to claim 1, wherein: The magnetic body has a restriction portion that restricts movement of the movable member, and Among the moments generated within the plane and centered at the contact position between the movable member and the restricting portion, the moment generated by gravity is larger than the moment generated by the urging means.

4. The driving device according to claim 3, wherein: The number of abutment positions between the movable member and the restricting portion is two, and Among the moments generated within the plane and centered at the contact position of the two contact portions close to the center of gravity of the movable member, the moment generated by gravity is larger than the moment generated by the force applying unit.

5. The driving device according to claim 1, wherein: At least three rolling members are arranged, and The force applying unit is arranged within a triangle formed by the rolling members.

6. The driving device according to claim 1, further comprising: a controller configured to control driving of the actuator, Wherein, the actuator comprises: a coil held by the movable member; a magnet held by the fixing member; a first detector configured to detect shaking information of the fixed member; and a second detector configured to detect relative position information of the movable member relative to the fixed member, and Wherein, based on the shaking information and the position information, the controller controls the driving of the movable member by controlling the current flowing through the coil.

7. A driving device, comprising: Fixed components; a movable member arranged to be relatively movable within a predetermined range within a plane relative to the fixed member; a plurality of rolling members disposed between the fixed member and the movable member; an actuator configured to drive the movable member; and a force applying unit, which is configured to include a magnet and a magnetic body and to apply force to the movable member toward the fixed member via the rolling member, The invention is characterized in that one of the magnet and the magnetic body is held by the movable member, and the other of the magnet and the magnetic body is held by the fixed member, and When the movable member moves by more than a predetermined amount from a reference position of the movable member relative to the fixed member, a part of the attractive force generated between the magnet and the magnetic body is used as a force in a direction to return the movable member to the reference position, and In a case where the movement amount is not greater than the predetermined value, the attractive force does not act as a force in a direction to return the movable member to the reference position.

8. An image blur correction device, comprising: Fixed components; a movable member that holds an image sensor or an image blur correction lens and is arranged to be relatively movable within a predetermined range within a plane with respect to the fixed member; a plurality of rolling members disposed between the fixed member and the movable member; an actuator configured to drive the movable member; and a force applying unit, which is configured to include a magnet and a magnetic body and to apply force to the movable member toward the fixed member via the rolling member, The invention is characterized in that one of the magnet and the magnetic body is held by the movable member, and the other of the magnet and the magnetic body is held by the fixed member, and When viewed from a direction orthogonal to the plane, a range in which the magnet can move when the actuator is driven to move the movable member does not protrude from an end portion of the magnetic body.

9. An image blur correction device, comprising: Fixed components; a movable member that holds an image sensor or an image blur correction lens and is arranged to be relatively movable within a predetermined range within a plane with respect to the fixed member; a plurality of rolling members disposed between the fixed member and the movable member; an actuator configured to drive the movable member; and a force applying unit, which is configured to include a magnet and a magnetic body and to apply force to the movable member toward the fixed member via the rolling member, The invention is characterized in that one of the magnet and the magnetic body is held by the movable member, and the other of the magnet and the magnetic body is held by the fixed member, and When the movable member moves by more than a predetermined amount from a reference position of the movable member relative to the fixed member, a part of the attractive force generated between the magnet and the magnetic body is used as a force in a direction to return the movable member to the reference position, and In a case where the movement amount is not greater than the predetermined value, the attractive force does not act as a force in a direction to return the movable member to the reference position.

10. A camera device, comprising: Fixed components; a movable member that holds an image sensor or an image blur correction lens and is arranged to be relatively movable within a predetermined range within a plane with respect to the fixed member; a plurality of rolling members disposed between the fixed member and the movable member; an actuator configured to drive the movable member; and a force applying unit, which is configured to include a magnet and a magnetic body and to apply force to the movable member toward the fixed member via the rolling member, The invention is characterized in that one of the magnet and the magnetic body is held by the movable member, and the other of the magnet and the magnetic body is held by the fixed member, and When viewed from a direction orthogonal to the plane, a range in which the magnet can move when the actuator is driven to move the movable member does not protrude from an end portion of the magnetic body.

11. The imaging device according to claim 10, further comprising: a connecting member which forms at least one opening when connected to the movable member; as well as, a first adhesive portion provided between a rear surface portion of the image sensor and an inner peripheral portion of the movable member, and Wherein, when viewed from a direction orthogonal to an imaging plane of the image sensor, the connecting member and the first adhesive portion do not overlap.

12. The imaging device according to claim 11, in, The first adhesive portion is provided in a pair of regions sandwiching the center of the image sensor in a plane parallel to the imaging surface.

13. The imaging device according to claim 11, in, A second adhesive portion is provided between the side surface portion of the image sensor and the side wall portion of the movable member.

14. The imaging device according to claim 13, in, The second adhesive portion is provided in a pair of regions sandwiching the center of the image sensor in a plane parallel to the imaging surface.

15. The imaging device according to claim 13, in, When viewed from a direction orthogonal to the imaging plane, the first adhesive portion and the second adhesive portion do not overlap.

16. The imaging device according to claim 13, in, The first adhesive portion and the second adhesive portion have different properties.

17. The imaging device according to claim 16, in, The first adhesive portion has higher adhesive strength at high temperature than the second adhesive portion.

18. The imaging device according to claim 16, in, When applied to the image sensor and the movable member, the viscosity of the liquid first adhesive used to form the first adhesive portion is different from the viscosity of the liquid second adhesive used to form the second adhesive portion.

19. The imaging device according to claim 18, in, The viscosity of the second adhesive is lower than the viscosity of the first adhesive.

20. A camera device, comprising: Fixed components; a movable member that holds an image sensor or an image blur correction lens and is arranged to be relatively movable within a predetermined range within a plane with respect to the fixed member; a plurality of rolling members disposed between the fixed member and the movable member; an actuator configured to drive the movable member; and a force applying unit, which is configured to include a magnet and a magnetic body and to apply force to the movable member toward the fixed member via the rolling member, The invention is characterized in that one of the magnet and the magnetic body is held by the movable member, and the other of the magnet and the magnetic body is held by the fixed member, and When the movable member moves by more than a predetermined amount from a reference position of the movable member relative to the fixed member, a part of the attractive force generated between the magnet and the magnetic body is used as a force in a direction to return the movable member to the reference position, and In a case where the movement amount is not greater than the predetermined value, the attractive force does not act as a force in a direction to return the movable member to the reference position.

Images